The invention relates to a process, and apparatus suited to perform the process, for the production of TPE foam profiles (thermoplastic elastomers with an olefin or styrene base, for instance) used in the building and automotive industries for window and door seals, for example.
Physical foaming of TPE foam profiles with a CFC-free blowing agent has not been possible on an industrial scale prior to the present invention. Numerous trials have been carried out in which blowing agents such as water or steam have been used to foam TPE. However, all previous attempts to produce a micro-fine mixture of such blowing agents and TPE have failed. The foam bubbles produced in this manner were either too large or very irregular so that the TPE base material, which is extremely weather resistant and easy to color, has not been capable of being produced industrially with a CFC-free blowing agent.